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From: furles on 4 Aug 2010 15:07
> Single mode interfaces are still till expensive, but
> coming down in price. Multi-mode won't handle much over 1Gb/s; single
> mode should hit more than 1Tb/s over 100 meters in a while.
>
> There probably is a specific type of connector that you should use for
> the fiber-optics, but I never figured out what it was.
>
> > strong competition, or is one the clear favorite into the future?

I think OM-1 is 220m with Gigait, 1000 base SX. OM-3 laser optimised
fibre will do 10 Gb, 10G base SR, at several hundred metres, I think
it's 300 m.

The longer wavelength optics normally used with single mode fibre are
significantly more expensive. It is possible to run 1000 base LX over
OM-1 and OM-2 multimode fiber using special mode conditioning patch
cords, but you'd probably only do this if you already had existing
older fibre installed.

As for connectors, ST were the most common at one time, but later
equipment tended to be SC. In more recent times the smaller LC
connector has become very common, and is probably the most popular.
It is also the recommend standard for use with OM-3 fibre. We've
found all of these connector types to be reliable, and MTRJ to be very
unreliable.
From: Cydrome Leader on 4 Aug 2010 15:54
In sci.electronics.equipment furles(a)mail.croydon.ac.uk wrote:
>> Single mode interfaces are still till expensive, but
>> coming down in price. Multi-mode won't handle much over 1Gb/s; single
>> mode should hit more than 1Tb/s over 100 meters in a while.
>>
>> There probably is a specific type of connector that you should use for
>> the fiber-optics, but I never figured out what it was.
>>
>> > strong competition, or is one the clear favorite into the future?
>
> I think OM-1 is 220m with Gigait, 1000 base SX. OM-3 laser optimised
> fibre will do 10 Gb, 10G base SR, at several hundred metres, I think
> it's 300 m.
>
> The longer wavelength optics normally used with single mode fibre are
> significantly more expensive. It is possible to run 1000 base LX over
> OM-1 and OM-2 multimode fiber using special mode conditioning patch
> cords, but you'd probably only do this if you already had existing
> older fibre installed.
>
> As for connectors, ST were the most common at one time, but later
> equipment tended to be SC. In more recent times the smaller LC
> connector has become very common, and is probably the most popular.
> It is also the recommend standard for use with OM-3 fibre. We've
> found all of these connector types to be reliable, and MTRJ to be very
> unreliable.

none of this matters.

nobody is going to be hooking up fiber devices in their home, no matter
what's in the walls already.
From: Bob E. on 4 Aug 2010 23:48
Thanks to all who contributed to this thread.

I'll be recommending the "datacom hose" ;-) , pull tubes to each room. That
way we can pull just CAT5e or CAT6 now and be done with it. Worries about
future media eliminated.

Cheers!

From: miso on 5 Aug 2010 03:12
On Aug 4, 9:33 am, Ecnerwal
<MyNameForw...(a)ReplaceWithMyVices.Com.invalid> wrote:
> Best and cheapest option is empty conduit (pull string optional - if the
> conduit is installed correctly, a shop vac, a rag or chunk of foam and a
> string should be able to install a pull string when you need one - I
> just installed pull strings in 2 330 foot runs of 2" conduit this way.)
> Then you only spend money on cables when you actually need cables, and
> you can always yank the old cables out and replace them with the latest
> thing when the latest thing comes along and you decide that you need it.
> Use large radius bends,  and provide access to pull boxes where needed.
> Run at least one more conduit than you know what you are doing with now,
> for something that comes along later.
>
> Not limited to electrical use, either - if at some point you decide you
> need compressed air in a room, you can run a compressed air hose through
> a conduit, for instance. Or use them as old fashioned speaking tubes...
>
> In multimode fiber, 50/125 is able to haul more data than 62.5/125. IMHO
> the only reason to use 62.5/125 is if you already have an installed base
> of 62.5/125 to maintain compatibility with. I have yet to see enough
> movement in singlemode pricing and connections to see much point in
> going there for anything short-haul.
>
> I also feel that for now, plain old Cat5e copper does pretty much
> everything that anyone is likely to need in a house, computer network
> wise. It's far faster than any offsite connection available, and most
> people don't have a lot of call for more than 1Gb/s rates around the
> house itself. Its also cheap enough to use part of the 500 or 1000 foot
> box for the Plain Old Telephone Service wires. Fiber is mainly of
> benefit going between buildings, where its immunity to lightning induced
> surges is a great benefit, and the ability to go much further than 100
> meters is of use. However, if the differential in price between Cat6A
> and Cat5e has come down enough, Cat6A offers possible future benefits.
> It's just that paying much for "future benefits" you never use is rather
> silly.
>
> Quick shopping results, 1000 feet, not exhaustive:
>
> Cat6A - 68 cents a foot plenum, 30 cents a foot not. (UTP version)
>
> Cat6 - 28 cents a foot plenum, 12 cents a foot not.
>
> Cat5e - 18 cents a foot plenum, 4 cents a foot not.
>
> By running it in dedicated conduit, you avoid any need for plenum-rated
> cable (though the cat 6 cable at some vendors was rated to a higher
> speed with plenum .vs. not plenum insulation on it.)
>
> --
> Cats, coffee, chocolate...vices to live by

I can't vouch for reality here, but I was told once a manufacturer can
make a certain grade of cable, in a short time all their cable is at
the grade. Basically if you are making the top grade, you want to be
ready to fill volume orders at the grade. I suppose this is true if
the quality depends on the twisting only and not dielectric material.

The other question of course is do you go shielded or unshielded.
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